Istanbul, April 1 () - The first batch of migrants is set to be sent back to Turkey from Greece on April 4, under the terms of an EU-Turkey readmission deal reached this month. However, the deal may experience delays due to unsolved organization issues regarding the readmission processes of the refugees. Turkey agreed with the EU this month to take back all migrants and refugees who cross to Greece illegally in exchange for financial aid, visa-free travel for Turks and “accelerated” EU membership talks. Meanwhile, the first batch of migrants could be delayed due to the excessive amount of refugees continuing to cross the Aegean Sea from Turkey to Greece in hope of a better life, even with Turkish and Greek officials working to stop arrivals at hotspots. With the weather starting to calm down once again after the harsh winter conditions, a total of 4,197 refugees have illegally landed on the Greek islands via Turkey from March 20, the starting date of the deal, to March 30. With another 926 refugees who reached Greece on March 19, this figure has exceeded 5,000. The hotspots, the islands of Lesbos and Chios, are reported to be full, while around 2,500 refugees in Lesbos and some 1,500 in Chios are being kept to be sent back to Turkey. Officials said that many steps in the readmission process were not clear yet. Topics still under debate vary from where the refugees would be taken from in Greece to where they would be sent in Turkey. In Brussels, EU spokeswoman Natasha Bertaud confirmed that April 4 was the “target day” of the new EU-Turkey scheme for “the return of asylum claims that have been declared inadmissible because they can get protection in Turkey and the start of the resettlement of Syrians from Turkey in the EU.” A Greek government source said the returns would “most probably” occur from Chios or Lesbos, the islands that have handled the bulk of arrivals from Turkey, and where thousands of migrants are being held in overcrowded registration centers. But the Greek official declined to give a number of readmissions. “We do not exclude that certain people will be returned April 4 but we cannot confirm that it will be this kind of number,” the official said. Greece’s deputy defense minister, Dimitris Vitsas, earlier this week said the returns to Turkey would take place “on six ships chartered by EU border agency Frontex.”